What are kidney stones?
Kidney stones develop either when there is too little urine volume or when the concentration of certain substances (known stone-forming substances) increases in the urine. Calcium oxalate and calcium phosphate are the two most common kinds of kidney stones. Kidney stones are more common in men than in women. About 11% of men and 6% of women in the US will get stones of the urinary tract at some point in life.
Certain dietary factors are linked to an increased risk of kidney stones. People who consume high levels of animal protein, sugar, and salt are at increased risk. Taking excessive amounts of vitamin D supplements can be associated with kidney stones. Consuming too little calcium can alter the balance of calcium and oxalate in the body and may lead to the development of oxalate stones.
A number of medical conditions can alter the body's metabolic states and cause a tendency to form kidney stones. Among these conditions associated with increased risk of kidney stones are gout, inflammatory bowel disease, intestinal bypass or ostomy surgery, hyperparathyroidism, some kidney diseases, and an inherited tendency to excrete too much calcium into the urine. Some medications can also raise the risk for getting kidney stones.
Medically reviewed by Michael Wolff, MD; American Board of Urology
National Kidney and Urologic Diseases. Kidney Stones in Adults.